Labor will attempt to stop the Coalition government raising Australia’s debt ceiling from $300bn to $500bn, calling for a compromise figure $400bn as politicians descended on Canberra for the opening of the 44th Parliament.

Parliament’s opening ceremony will take place on Tuesday before the Coalition government introduces its first piece of legislation, a bill to repeal the carbon tax on Wednesday.

The Coalition is also introducing legislation to increase the nation’s debt limit to $500bn, however, Labor flagged its opposition to the rise.

Caucus instead committed to limiting the debt ceiling on the grounds that the latest publicly available budget estimates – the Pre-election Economic and Fiscal Outlook – suggested a limit of $400bn was adequate.

Labor’s shadow treasurer Chris Bowen urged the Abbott Government to release the Mid-Year Economic and Fiscal Outlook if a greater debt limit was required.

“Australians aren’t able to get new mortgages or credit cards without submitting their personal financial information for scrutiny, so it’s a bit rich for Mr Hockey to take the public credit card to half a trillion dollars without updated budget estimates,” Bowen said.

“He’s asking Australians to blindly tick off a $200 billion increase in the nation’s credit card limit without showing them why.”

As members and senators descended on Canberra ahead of the opening, Tony Abbott urged Coalition members to be as disciplined in government as they were in opposition.

His comments come as pressure mounts from National and country Liberal party members on Treasurer Joe Hockey to block the sale of GrainCorp to Archer Daniels Midland for $3.4bn.

In welcoming new Coalition MPs, Abbott stressed the need for “unity and collegiality” reminding them that politics was a “hard and unforgiving business”.

Deputy prime minister and National party leader Warren Truss – who has himself urged Hockey not to approve the takeover bid – also addressed the joint party room meeting though it is understood GrainCorp was not discussed.

The Abbott government will introduce bills relating to the carbon tax repeal, the debt ceiling increase and the repeal of the Minerals Resource Rent Tax (MRRT) as a matter of priority in the first week of sitting.

Hockey is hoping to pass the debt ceiling limit by the end of the first week of sitting as Treasury has advised the current $300bn limit will be reached by December 12 this year, leaving the possibility open that Australia could default if an increase is not granted.

Labor’s first caucus meeting endorsed the shadow cabinet position to oppose the repeal of the carbon tax, previously announced by leader Bill Shorten, unless it is replaced with an emissions trading scheme.

Labor will also oppose any repeal of the MRRT. By repealing the mining tax, the Coalition has committed to dump related expenditure of the school kids’ bonus and low-income super contribution.

In his first address of the new parliament, Shorten will evoke the achievements of Labor governments, including superannuation, the National Disability Insurance Scheme, the aged pension and the floating of the Australian dollar.

The opening ceremony includes a welcome to country before the deputy of the governor general and high court chief justice Robert French officially opens the Parliament. The House of Representatives will nominate and then vote to elect a speaker, widely expected to be former Howard government minister Bronwyn Bishop.

The governor general, Quentin Bryce, will then inspect the guard and will address the parliament on Tuesday afternoon.